25 minutes · AC9MFN05 and AC9MFA01 (practical change and pattern review); partial evidence · educator review pending
Success: The child models a named addition or removal and continues a repeating pattern by returning to its unit.
Prepare per pair: ten counters, two trays, circle/square cards, R8–R10 and change/pattern mat.
- Retrieve, 3 min. Show five objects and move two to a tray. Ask how many remain on the original mat and how many exist across both places: three and five.
- Model, 6 min. Act R8: six library cards, three more join, nine now. Count the final set. Then lay circle–square three times, bracket circle–square and continue circle, square, circle. Explain that the number check uses the named set; the pattern check uses the repeated part.
- Guided game, 9 min. Pairs enact R8 and R9 (nine shelf cards, four moved to a tray), then build an AB or AAB pattern from original shape cards. One directs and explains; the other checks; swap. Quiet symbol routes replace sound or movement.
- Fresh try, 4 min. “Five paper shapes are here; two more join. How many now?” Then show star–star–moon twice and ask for the next three. Use objects/cards before an equation.
- Check, 3 min. Ask for one way to verify each result. Key: R8 6+3=9; R9 9−4=5 on shelf with all nine still present; R10 unit circle–square, next circle/square/circle; fresh 5+2=7 and next star/star/moon.
If the child always adds two story numbers: Re-enact the removal and count only the shelf boundary. If they alternate star/moon, mark each complete star–star–moon unit and begin it again.
Access and record: Grippable objects, large/tactile shape cards, plain-text/read-aloud story, AAC and directed placement are available. Record action/result and pattern unit/continuation separately, with prompts.